Field of the Invention
This invention belongs to the technical field of liquid crystal display, in particular, to an edge type backlight module and a liquid crystal display device.
Description of Related Art
With the evolution of optical and semiconductor technology, also led to the flat panel display (Flat Panel Display) to flourish, and in many flat panel displays, liquid crystal display device (Liquid Crystal Display, referred to as LCD) because of its superior characteristics in high space utilization efficiency, low power consumption, no radiation, and low electromagnetic interference and so on, has become the mainstream of the market.
The liquid crystal display device generally includes a liquid crystal display panel (Liquid Crystal Panel) and the backlight module (Back Light Module, abbreviated BL). Since the LCD panel itself does not have the characteristics of self-luminous, it must utilize the LCD backlight module providing the necessary surface light source, then the image can be displayed via a surface light source provided by the backlight module to liquid crystal display panel.
Backlight module is divided into two different type including edge type backlight module and direct type backlight module according to the position of the light source. The direct type backlight module light source (e.g., a cathode fluorescent lamp (Cold Cathode Fluorescent Lamp, CCFL) or light emitting diodes (Light Emitting Diode, LED)) is disposed behind the liquid crystal display panel, so a surface light source is formed directly to the liquid crystal display panel. The edge type backlight module is the light source (such as LED light strip (Light Bar)) provided in the LCD backplane side of the rear edge of the panel generally, the light emitted from the LED strip entering light guide plate (Light Guide Plate, LGP) from its side, emitting from the light guide plate exit surface after diffusion and emission by the optical film module, then set to form the surface light source and to be supplied to the liquid crystal display panel. However, the LED light bar is set at the edge of the liquid crystal display panel in the rear side of the backplane for the edge type backlight module, resulting to a higher temperature on the edge of the back plate. When the liquid crystal display panel is placed on top of the backlight module, which the edge of the COF (Chip On Film) will be at a higher temperature condition, so the reliability of COF degrades significantly.